diff mbox

[v2] cifs: extend the buffer length enought for sprintf() using

Message ID 51E88FF0.2010101@asianux.com (mailing list archive)
State New, archived
Headers show

Commit Message

Chen Gang July 19, 2013, 1:01 a.m. UTC
For cifs_set_cifscreds() in "fs/cifs/connect.c", 'desc' buffer length
is 'CIFSCREDS_DESC_SIZE' (56 is less than 256), and 'ses->domainName'
length may be "255 + '\0'".

The related sprintf() may cause memory overflow, so need extend related
buffer enough to hold all things.

It is also necessary to be sure of 'ses->domainName' must be less than
256, and define the related macro instead of hard code number '256'.

Signed-off-by: Chen Gang <gang.chen@asianux.com>
---
 fs/cifs/cifsencrypt.c |    2 +-
 fs/cifs/cifsglob.h    |    1 +
 fs/cifs/connect.c     |    7 ++++---
 fs/cifs/sess.c        |    6 +++---
 4 files changed, 9 insertions(+), 7 deletions(-)

Comments

Jeff Layton July 19, 2013, 10:45 a.m. UTC | #1
On Fri, 19 Jul 2013 09:01:36 +0800
Chen Gang <gang.chen@asianux.com> wrote:

> For cifs_set_cifscreds() in "fs/cifs/connect.c", 'desc' buffer length
> is 'CIFSCREDS_DESC_SIZE' (56 is less than 256), and 'ses->domainName'
> length may be "255 + '\0'".
> 
> The related sprintf() may cause memory overflow, so need extend related
> buffer enough to hold all things.
> 
> It is also necessary to be sure of 'ses->domainName' must be less than
> 256, and define the related macro instead of hard code number '256'.
> 
> Signed-off-by: Chen Gang <gang.chen@asianux.com>
> ---
>  fs/cifs/cifsencrypt.c |    2 +-
>  fs/cifs/cifsglob.h    |    1 +
>  fs/cifs/connect.c     |    7 ++++---
>  fs/cifs/sess.c        |    6 +++---
>  4 files changed, 9 insertions(+), 7 deletions(-)
> 
> diff --git a/fs/cifs/cifsencrypt.c b/fs/cifs/cifsencrypt.c
> index 45e57cc..bb84d7c 100644
> --- a/fs/cifs/cifsencrypt.c
> +++ b/fs/cifs/cifsencrypt.c
> @@ -421,7 +421,7 @@ find_domain_name(struct cifs_ses *ses, const struct nls_table *nls_cp)
>  		if (blobptr + attrsize > blobend)
>  			break;
>  		if (type == NTLMSSP_AV_NB_DOMAIN_NAME) {
> -			if (!attrsize)
> +			if (!attrsize || attrsize >= MAX_DOMAINNAME_SIZE)
>  				break;
>  			if (!ses->domainName) {
>  				ses->domainName =
> diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
> index 33f17ed..64bb4c5 100644
> --- a/fs/cifs/cifsglob.h
> +++ b/fs/cifs/cifsglob.h
> @@ -44,6 +44,7 @@
>  #define MAX_TREE_SIZE (2 + MAX_SERVER_SIZE + 1 + MAX_SHARE_SIZE + 1)
>  #define MAX_SERVER_SIZE 15
>  #define MAX_SHARE_SIZE 80
> +#define MAX_DOMAINNAME_SIZE 256	/* maximum fully qualified domain name (FQDN) */
>  #define MAX_USERNAME_SIZE 256	/* reasonable maximum for current servers */
>  #define MAX_PASSWORD_SIZE 512	/* max for windows seems to be 256 wide chars */
>  
> diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
> index fa68813..3f9dcf7 100644
> --- a/fs/cifs/connect.c
> +++ b/fs/cifs/connect.c
> @@ -1675,7 +1675,8 @@ cifs_parse_mount_options(const char *mountdata, const char *devname,
>  			if (string == NULL)
>  				goto out_nomem;
>  
> -			if (strnlen(string, 256) == 256) {
> +			if (strnlen(string, MAX_DOMAINNAME_SIZE)
> +					== MAX_DOMAINNAME_SIZE) {
>  				printk(KERN_WARNING "CIFS: domain name too"
>  						    " long\n");
>  				goto cifs_parse_mount_err;
> @@ -2276,8 +2277,8 @@ cifs_put_smb_ses(struct cifs_ses *ses)
>  
>  #ifdef CONFIG_KEYS
>  
> -/* strlen("cifs:a:") + INET6_ADDRSTRLEN + 1 */
> -#define CIFSCREDS_DESC_SIZE (7 + INET6_ADDRSTRLEN + 1)
> +/* strlen("cifs:a:") + MAX_DOMAINNAME_SIZE + 1 */
> +#define CIFSCREDS_DESC_SIZE (7 + MAX_DOMAINNAME_SIZE + 1)
>  
>  /* Populate username and pw fields from keyring if possible */
>  static int
> diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c
> index 79358e3..57b1537 100644
> --- a/fs/cifs/sess.c
> +++ b/fs/cifs/sess.c
> @@ -197,7 +197,7 @@ static void unicode_domain_string(char **pbcc_area, struct cifs_ses *ses,
>  		bytes_ret = 0;
>  	} else
>  		bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, ses->domainName,
> -					    256, nls_cp);
> +					    MAX_DOMAINNAME_SIZE, nls_cp);
>  	bcc_ptr += 2 * bytes_ret;
>  	bcc_ptr += 2;  /* account for null terminator */
>  
> @@ -255,8 +255,8 @@ static void ascii_ssetup_strings(char **pbcc_area, struct cifs_ses *ses,
>  
>  	/* copy domain */
>  	if (ses->domainName != NULL) {
> -		strncpy(bcc_ptr, ses->domainName, 256);
> -		bcc_ptr += strnlen(ses->domainName, 256);
> +		strncpy(bcc_ptr, ses->domainName, MAX_DOMAINNAME_SIZE);
> +		bcc_ptr += strnlen(ses->domainName, MAX_DOMAINNAME_SIZE);
>  	} /* else we will send a null domain name
>  	     so the server will default to its own domain */
>  	*bcc_ptr = 0;

Looks good...

Reviewed-by: Jeff Layton <jlayton@redhat.com>
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Steve French July 19, 2013, 3:46 p.m. UTC | #2
merged into cifs-2.6.git

On Fri, Jul 19, 2013 at 5:45 AM, Jeff Layton <jlayton@redhat.com> wrote:
> On Fri, 19 Jul 2013 09:01:36 +0800
> Chen Gang <gang.chen@asianux.com> wrote:
>
>> For cifs_set_cifscreds() in "fs/cifs/connect.c", 'desc' buffer length
>> is 'CIFSCREDS_DESC_SIZE' (56 is less than 256), and 'ses->domainName'
>> length may be "255 + '\0'".
>>
>> The related sprintf() may cause memory overflow, so need extend related
>> buffer enough to hold all things.
>>
>> It is also necessary to be sure of 'ses->domainName' must be less than
>> 256, and define the related macro instead of hard code number '256'.
>>
>> Signed-off-by: Chen Gang <gang.chen@asianux.com>
>> ---
>>  fs/cifs/cifsencrypt.c |    2 +-
>>  fs/cifs/cifsglob.h    |    1 +
>>  fs/cifs/connect.c     |    7 ++++---
>>  fs/cifs/sess.c        |    6 +++---
>>  4 files changed, 9 insertions(+), 7 deletions(-)
>>
>> diff --git a/fs/cifs/cifsencrypt.c b/fs/cifs/cifsencrypt.c
>> index 45e57cc..bb84d7c 100644
>> --- a/fs/cifs/cifsencrypt.c
>> +++ b/fs/cifs/cifsencrypt.c
>> @@ -421,7 +421,7 @@ find_domain_name(struct cifs_ses *ses, const struct nls_table *nls_cp)
>>               if (blobptr + attrsize > blobend)
>>                       break;
>>               if (type == NTLMSSP_AV_NB_DOMAIN_NAME) {
>> -                     if (!attrsize)
>> +                     if (!attrsize || attrsize >= MAX_DOMAINNAME_SIZE)
>>                               break;
>>                       if (!ses->domainName) {
>>                               ses->domainName =
>> diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
>> index 33f17ed..64bb4c5 100644
>> --- a/fs/cifs/cifsglob.h
>> +++ b/fs/cifs/cifsglob.h
>> @@ -44,6 +44,7 @@
>>  #define MAX_TREE_SIZE (2 + MAX_SERVER_SIZE + 1 + MAX_SHARE_SIZE + 1)
>>  #define MAX_SERVER_SIZE 15
>>  #define MAX_SHARE_SIZE 80
>> +#define MAX_DOMAINNAME_SIZE 256      /* maximum fully qualified domain name (FQDN) */
>>  #define MAX_USERNAME_SIZE 256        /* reasonable maximum for current servers */
>>  #define MAX_PASSWORD_SIZE 512        /* max for windows seems to be 256 wide chars */
>>
>> diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
>> index fa68813..3f9dcf7 100644
>> --- a/fs/cifs/connect.c
>> +++ b/fs/cifs/connect.c
>> @@ -1675,7 +1675,8 @@ cifs_parse_mount_options(const char *mountdata, const char *devname,
>>                       if (string == NULL)
>>                               goto out_nomem;
>>
>> -                     if (strnlen(string, 256) == 256) {
>> +                     if (strnlen(string, MAX_DOMAINNAME_SIZE)
>> +                                     == MAX_DOMAINNAME_SIZE) {
>>                               printk(KERN_WARNING "CIFS: domain name too"
>>                                                   " long\n");
>>                               goto cifs_parse_mount_err;
>> @@ -2276,8 +2277,8 @@ cifs_put_smb_ses(struct cifs_ses *ses)
>>
>>  #ifdef CONFIG_KEYS
>>
>> -/* strlen("cifs:a:") + INET6_ADDRSTRLEN + 1 */
>> -#define CIFSCREDS_DESC_SIZE (7 + INET6_ADDRSTRLEN + 1)
>> +/* strlen("cifs:a:") + MAX_DOMAINNAME_SIZE + 1 */
>> +#define CIFSCREDS_DESC_SIZE (7 + MAX_DOMAINNAME_SIZE + 1)
>>
>>  /* Populate username and pw fields from keyring if possible */
>>  static int
>> diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c
>> index 79358e3..57b1537 100644
>> --- a/fs/cifs/sess.c
>> +++ b/fs/cifs/sess.c
>> @@ -197,7 +197,7 @@ static void unicode_domain_string(char **pbcc_area, struct cifs_ses *ses,
>>               bytes_ret = 0;
>>       } else
>>               bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, ses->domainName,
>> -                                         256, nls_cp);
>> +                                         MAX_DOMAINNAME_SIZE, nls_cp);
>>       bcc_ptr += 2 * bytes_ret;
>>       bcc_ptr += 2;  /* account for null terminator */
>>
>> @@ -255,8 +255,8 @@ static void ascii_ssetup_strings(char **pbcc_area, struct cifs_ses *ses,
>>
>>       /* copy domain */
>>       if (ses->domainName != NULL) {
>> -             strncpy(bcc_ptr, ses->domainName, 256);
>> -             bcc_ptr += strnlen(ses->domainName, 256);
>> +             strncpy(bcc_ptr, ses->domainName, MAX_DOMAINNAME_SIZE);
>> +             bcc_ptr += strnlen(ses->domainName, MAX_DOMAINNAME_SIZE);
>>       } /* else we will send a null domain name
>>            so the server will default to its own domain */
>>       *bcc_ptr = 0;
>
> Looks good...
>
> Reviewed-by: Jeff Layton <jlayton@redhat.com>
Steve French July 19, 2013, 4:18 p.m. UTC | #3
Added CC: <stable@vger.kernel.org>

On Fri, Jul 19, 2013 at 10:46 AM, Steve French <smfrench@gmail.com> wrote:
> merged into cifs-2.6.git
>
> On Fri, Jul 19, 2013 at 5:45 AM, Jeff Layton <jlayton@redhat.com> wrote:
>> On Fri, 19 Jul 2013 09:01:36 +0800
>> Chen Gang <gang.chen@asianux.com> wrote:
>>
>>> For cifs_set_cifscreds() in "fs/cifs/connect.c", 'desc' buffer length
>>> is 'CIFSCREDS_DESC_SIZE' (56 is less than 256), and 'ses->domainName'
>>> length may be "255 + '\0'".
>>>
>>> The related sprintf() may cause memory overflow, so need extend related
>>> buffer enough to hold all things.
>>>
>>> It is also necessary to be sure of 'ses->domainName' must be less than
>>> 256, and define the related macro instead of hard code number '256'.
>>>
>>> Signed-off-by: Chen Gang <gang.chen@asianux.com>
>>> ---
>>>  fs/cifs/cifsencrypt.c |    2 +-
>>>  fs/cifs/cifsglob.h    |    1 +
>>>  fs/cifs/connect.c     |    7 ++++---
>>>  fs/cifs/sess.c        |    6 +++---
>>>  4 files changed, 9 insertions(+), 7 deletions(-)
>>>
>>> diff --git a/fs/cifs/cifsencrypt.c b/fs/cifs/cifsencrypt.c
>>> index 45e57cc..bb84d7c 100644
>>> --- a/fs/cifs/cifsencrypt.c
>>> +++ b/fs/cifs/cifsencrypt.c
>>> @@ -421,7 +421,7 @@ find_domain_name(struct cifs_ses *ses, const struct nls_table *nls_cp)
>>>               if (blobptr + attrsize > blobend)
>>>                       break;
>>>               if (type == NTLMSSP_AV_NB_DOMAIN_NAME) {
>>> -                     if (!attrsize)
>>> +                     if (!attrsize || attrsize >= MAX_DOMAINNAME_SIZE)
>>>                               break;
>>>                       if (!ses->domainName) {
>>>                               ses->domainName =
>>> diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
>>> index 33f17ed..64bb4c5 100644
>>> --- a/fs/cifs/cifsglob.h
>>> +++ b/fs/cifs/cifsglob.h
>>> @@ -44,6 +44,7 @@
>>>  #define MAX_TREE_SIZE (2 + MAX_SERVER_SIZE + 1 + MAX_SHARE_SIZE + 1)
>>>  #define MAX_SERVER_SIZE 15
>>>  #define MAX_SHARE_SIZE 80
>>> +#define MAX_DOMAINNAME_SIZE 256      /* maximum fully qualified domain name (FQDN) */
>>>  #define MAX_USERNAME_SIZE 256        /* reasonable maximum for current servers */
>>>  #define MAX_PASSWORD_SIZE 512        /* max for windows seems to be 256 wide chars */
>>>
>>> diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
>>> index fa68813..3f9dcf7 100644
>>> --- a/fs/cifs/connect.c
>>> +++ b/fs/cifs/connect.c
>>> @@ -1675,7 +1675,8 @@ cifs_parse_mount_options(const char *mountdata, const char *devname,
>>>                       if (string == NULL)
>>>                               goto out_nomem;
>>>
>>> -                     if (strnlen(string, 256) == 256) {
>>> +                     if (strnlen(string, MAX_DOMAINNAME_SIZE)
>>> +                                     == MAX_DOMAINNAME_SIZE) {
>>>                               printk(KERN_WARNING "CIFS: domain name too"
>>>                                                   " long\n");
>>>                               goto cifs_parse_mount_err;
>>> @@ -2276,8 +2277,8 @@ cifs_put_smb_ses(struct cifs_ses *ses)
>>>
>>>  #ifdef CONFIG_KEYS
>>>
>>> -/* strlen("cifs:a:") + INET6_ADDRSTRLEN + 1 */
>>> -#define CIFSCREDS_DESC_SIZE (7 + INET6_ADDRSTRLEN + 1)
>>> +/* strlen("cifs:a:") + MAX_DOMAINNAME_SIZE + 1 */
>>> +#define CIFSCREDS_DESC_SIZE (7 + MAX_DOMAINNAME_SIZE + 1)
>>>
>>>  /* Populate username and pw fields from keyring if possible */
>>>  static int
>>> diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c
>>> index 79358e3..57b1537 100644
>>> --- a/fs/cifs/sess.c
>>> +++ b/fs/cifs/sess.c
>>> @@ -197,7 +197,7 @@ static void unicode_domain_string(char **pbcc_area, struct cifs_ses *ses,
>>>               bytes_ret = 0;
>>>       } else
>>>               bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, ses->domainName,
>>> -                                         256, nls_cp);
>>> +                                         MAX_DOMAINNAME_SIZE, nls_cp);
>>>       bcc_ptr += 2 * bytes_ret;
>>>       bcc_ptr += 2;  /* account for null terminator */
>>>
>>> @@ -255,8 +255,8 @@ static void ascii_ssetup_strings(char **pbcc_area, struct cifs_ses *ses,
>>>
>>>       /* copy domain */
>>>       if (ses->domainName != NULL) {
>>> -             strncpy(bcc_ptr, ses->domainName, 256);
>>> -             bcc_ptr += strnlen(ses->domainName, 256);
>>> +             strncpy(bcc_ptr, ses->domainName, MAX_DOMAINNAME_SIZE);
>>> +             bcc_ptr += strnlen(ses->domainName, MAX_DOMAINNAME_SIZE);
>>>       } /* else we will send a null domain name
>>>            so the server will default to its own domain */
>>>       *bcc_ptr = 0;
>>
>> Looks good...
>>
>> Reviewed-by: Jeff Layton <jlayton@redhat.com>
>
>
>
> --
> Thanks,
>
> Steve
Chen Gang July 22, 2013, 12:29 a.m. UTC | #4
On 07/19/2013 06:45 PM, Jeff Layton wrote:
> On Fri, 19 Jul 2013 09:01:36 +0800
> Chen Gang <gang.chen@asianux.com> wrote:
> 
>> For cifs_set_cifscreds() in "fs/cifs/connect.c", 'desc' buffer length
>> is 'CIFSCREDS_DESC_SIZE' (56 is less than 256), and 'ses->domainName'
>> length may be "255 + '\0'".
>>
>> The related sprintf() may cause memory overflow, so need extend related
>> buffer enough to hold all things.
>>
>> It is also necessary to be sure of 'ses->domainName' must be less than
>> 256, and define the related macro instead of hard code number '256'.
>>
>> Signed-off-by: Chen Gang <gang.chen@asianux.com>
>> ---
>>  fs/cifs/cifsencrypt.c |    2 +-
>>  fs/cifs/cifsglob.h    |    1 +
>>  fs/cifs/connect.c     |    7 ++++---
>>  fs/cifs/sess.c        |    6 +++---
>>  4 files changed, 9 insertions(+), 7 deletions(-)
>>
>> diff --git a/fs/cifs/cifsencrypt.c b/fs/cifs/cifsencrypt.c
>> index 45e57cc..bb84d7c 100644
>> --- a/fs/cifs/cifsencrypt.c
>> +++ b/fs/cifs/cifsencrypt.c
>> @@ -421,7 +421,7 @@ find_domain_name(struct cifs_ses *ses, const struct nls_table *nls_cp)
>>  		if (blobptr + attrsize > blobend)
>>  			break;
>>  		if (type == NTLMSSP_AV_NB_DOMAIN_NAME) {
>> -			if (!attrsize)
>> +			if (!attrsize || attrsize >= MAX_DOMAINNAME_SIZE)
>>  				break;
>>  			if (!ses->domainName) {
>>  				ses->domainName =
>> diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
>> index 33f17ed..64bb4c5 100644
>> --- a/fs/cifs/cifsglob.h
>> +++ b/fs/cifs/cifsglob.h
>> @@ -44,6 +44,7 @@
>>  #define MAX_TREE_SIZE (2 + MAX_SERVER_SIZE + 1 + MAX_SHARE_SIZE + 1)
>>  #define MAX_SERVER_SIZE 15
>>  #define MAX_SHARE_SIZE 80
>> +#define MAX_DOMAINNAME_SIZE 256	/* maximum fully qualified domain name (FQDN) */
>>  #define MAX_USERNAME_SIZE 256	/* reasonable maximum for current servers */
>>  #define MAX_PASSWORD_SIZE 512	/* max for windows seems to be 256 wide chars */
>>  
>> diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
>> index fa68813..3f9dcf7 100644
>> --- a/fs/cifs/connect.c
>> +++ b/fs/cifs/connect.c
>> @@ -1675,7 +1675,8 @@ cifs_parse_mount_options(const char *mountdata, const char *devname,
>>  			if (string == NULL)
>>  				goto out_nomem;
>>  
>> -			if (strnlen(string, 256) == 256) {
>> +			if (strnlen(string, MAX_DOMAINNAME_SIZE)
>> +					== MAX_DOMAINNAME_SIZE) {
>>  				printk(KERN_WARNING "CIFS: domain name too"
>>  						    " long\n");
>>  				goto cifs_parse_mount_err;
>> @@ -2276,8 +2277,8 @@ cifs_put_smb_ses(struct cifs_ses *ses)
>>  
>>  #ifdef CONFIG_KEYS
>>  
>> -/* strlen("cifs:a:") + INET6_ADDRSTRLEN + 1 */
>> -#define CIFSCREDS_DESC_SIZE (7 + INET6_ADDRSTRLEN + 1)
>> +/* strlen("cifs:a:") + MAX_DOMAINNAME_SIZE + 1 */
>> +#define CIFSCREDS_DESC_SIZE (7 + MAX_DOMAINNAME_SIZE + 1)
>>  
>>  /* Populate username and pw fields from keyring if possible */
>>  static int
>> diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c
>> index 79358e3..57b1537 100644
>> --- a/fs/cifs/sess.c
>> +++ b/fs/cifs/sess.c
>> @@ -197,7 +197,7 @@ static void unicode_domain_string(char **pbcc_area, struct cifs_ses *ses,
>>  		bytes_ret = 0;
>>  	} else
>>  		bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, ses->domainName,
>> -					    256, nls_cp);
>> +					    MAX_DOMAINNAME_SIZE, nls_cp);
>>  	bcc_ptr += 2 * bytes_ret;
>>  	bcc_ptr += 2;  /* account for null terminator */
>>  
>> @@ -255,8 +255,8 @@ static void ascii_ssetup_strings(char **pbcc_area, struct cifs_ses *ses,
>>  
>>  	/* copy domain */
>>  	if (ses->domainName != NULL) {
>> -		strncpy(bcc_ptr, ses->domainName, 256);
>> -		bcc_ptr += strnlen(ses->domainName, 256);
>> +		strncpy(bcc_ptr, ses->domainName, MAX_DOMAINNAME_SIZE);
>> +		bcc_ptr += strnlen(ses->domainName, MAX_DOMAINNAME_SIZE);
>>  	} /* else we will send a null domain name
>>  	     so the server will default to its own domain */
>>  	*bcc_ptr = 0;
> 
> Looks good...
> 
> Reviewed-by: Jeff Layton <jlayton@redhat.com>
> 
> 

Thanks.
Chen Gang July 22, 2013, 1:21 a.m. UTC | #5
On 07/19/2013 11:46 PM, Steve French wrote:
> merged into cifs-2.6.git
> 

Thanks.

> On Fri, Jul 19, 2013 at 5:45 AM, Jeff Layton <jlayton@redhat.com> wrote:
>> > On Fri, 19 Jul 2013 09:01:36 +0800
>> > Chen Gang <gang.chen@asianux.com> wrote:
>> >
>>> >> For cifs_set_cifscreds() in "fs/cifs/connect.c", 'desc' buffer length
>>> >> is 'CIFSCREDS_DESC_SIZE' (56 is less than 256), and 'ses->domainName'
>>> >> length may be "255 + '\0'".
>>> >>
>>> >> The related sprintf() may cause memory overflow, so need extend related
>>> >> buffer enough to hold all things.
>>> >>
>>> >> It is also necessary to be sure of 'ses->domainName' must be less than
>>> >> 256, and define the related macro instead of hard code number '256'.
>>> >>
>>> >> Signed-off-by: Chen Gang <gang.chen@asianux.com>
>>> >> ---
>>> >>  fs/cifs/cifsencrypt.c |    2 +-
>>> >>  fs/cifs/cifsglob.h    |    1 +
>>> >>  fs/cifs/connect.c     |    7 ++++---
>>> >>  fs/cifs/sess.c        |    6 +++---
>>> >>  4 files changed, 9 insertions(+), 7 deletions(-)
>>> >>
>>> >> diff --git a/fs/cifs/cifsencrypt.c b/fs/cifs/cifsencrypt.c
>>> >> index 45e57cc..bb84d7c 100644
>>> >> --- a/fs/cifs/cifsencrypt.c
>>> >> +++ b/fs/cifs/cifsencrypt.c
>>> >> @@ -421,7 +421,7 @@ find_domain_name(struct cifs_ses *ses, const struct nls_table *nls_cp)
>>> >>               if (blobptr + attrsize > blobend)
>>> >>                       break;
>>> >>               if (type == NTLMSSP_AV_NB_DOMAIN_NAME) {
>>> >> -                     if (!attrsize)
>>> >> +                     if (!attrsize || attrsize >= MAX_DOMAINNAME_SIZE)
>>> >>                               break;
>>> >>                       if (!ses->domainName) {
>>> >>                               ses->domainName =
>>> >> diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
>>> >> index 33f17ed..64bb4c5 100644
>>> >> --- a/fs/cifs/cifsglob.h
>>> >> +++ b/fs/cifs/cifsglob.h
>>> >> @@ -44,6 +44,7 @@
>>> >>  #define MAX_TREE_SIZE (2 + MAX_SERVER_SIZE + 1 + MAX_SHARE_SIZE + 1)
>>> >>  #define MAX_SERVER_SIZE 15
>>> >>  #define MAX_SHARE_SIZE 80
>>> >> +#define MAX_DOMAINNAME_SIZE 256      /* maximum fully qualified domain name (FQDN) */
>>> >>  #define MAX_USERNAME_SIZE 256        /* reasonable maximum for current servers */
>>> >>  #define MAX_PASSWORD_SIZE 512        /* max for windows seems to be 256 wide chars */
>>> >>
>>> >> diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
>>> >> index fa68813..3f9dcf7 100644
>>> >> --- a/fs/cifs/connect.c
>>> >> +++ b/fs/cifs/connect.c
>>> >> @@ -1675,7 +1675,8 @@ cifs_parse_mount_options(const char *mountdata, const char *devname,
>>> >>                       if (string == NULL)
>>> >>                               goto out_nomem;
>>> >>
>>> >> -                     if (strnlen(string, 256) == 256) {
>>> >> +                     if (strnlen(string, MAX_DOMAINNAME_SIZE)
>>> >> +                                     == MAX_DOMAINNAME_SIZE) {
>>> >>                               printk(KERN_WARNING "CIFS: domain name too"
>>> >>                                                   " long\n");
>>> >>                               goto cifs_parse_mount_err;
>>> >> @@ -2276,8 +2277,8 @@ cifs_put_smb_ses(struct cifs_ses *ses)
>>> >>
>>> >>  #ifdef CONFIG_KEYS
>>> >>
>>> >> -/* strlen("cifs:a:") + INET6_ADDRSTRLEN + 1 */
>>> >> -#define CIFSCREDS_DESC_SIZE (7 + INET6_ADDRSTRLEN + 1)
>>> >> +/* strlen("cifs:a:") + MAX_DOMAINNAME_SIZE + 1 */
>>> >> +#define CIFSCREDS_DESC_SIZE (7 + MAX_DOMAINNAME_SIZE + 1)
>>> >>
>>> >>  /* Populate username and pw fields from keyring if possible */
>>> >>  static int
>>> >> diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c
>>> >> index 79358e3..57b1537 100644
>>> >> --- a/fs/cifs/sess.c
>>> >> +++ b/fs/cifs/sess.c
>>> >> @@ -197,7 +197,7 @@ static void unicode_domain_string(char **pbcc_area, struct cifs_ses *ses,
>>> >>               bytes_ret = 0;
>>> >>       } else
>>> >>               bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, ses->domainName,
>>> >> -                                         256, nls_cp);
>>> >> +                                         MAX_DOMAINNAME_SIZE, nls_cp);
>>> >>       bcc_ptr += 2 * bytes_ret;
>>> >>       bcc_ptr += 2;  /* account for null terminator */
>>> >>
>>> >> @@ -255,8 +255,8 @@ static void ascii_ssetup_strings(char **pbcc_area, struct cifs_ses *ses,
>>> >>
>>> >>       /* copy domain */
>>> >>       if (ses->domainName != NULL) {
>>> >> -             strncpy(bcc_ptr, ses->domainName, 256);
>>> >> -             bcc_ptr += strnlen(ses->domainName, 256);
>>> >> +             strncpy(bcc_ptr, ses->domainName, MAX_DOMAINNAME_SIZE);
>>> >> +             bcc_ptr += strnlen(ses->domainName, MAX_DOMAINNAME_SIZE);
>>> >>       } /* else we will send a null domain name
>>> >>            so the server will default to its own domain */
>>> >>       *bcc_ptr = 0;
>> >
>> > Looks good...
>> >
>> > Reviewed-by: Jeff Layton <jlayton@redhat.com>
> 
> 
> -- Thanks, Steve
>
diff mbox

Patch

diff --git a/fs/cifs/cifsencrypt.c b/fs/cifs/cifsencrypt.c
index 45e57cc..bb84d7c 100644
--- a/fs/cifs/cifsencrypt.c
+++ b/fs/cifs/cifsencrypt.c
@@ -421,7 +421,7 @@  find_domain_name(struct cifs_ses *ses, const struct nls_table *nls_cp)
 		if (blobptr + attrsize > blobend)
 			break;
 		if (type == NTLMSSP_AV_NB_DOMAIN_NAME) {
-			if (!attrsize)
+			if (!attrsize || attrsize >= MAX_DOMAINNAME_SIZE)
 				break;
 			if (!ses->domainName) {
 				ses->domainName =
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index 33f17ed..64bb4c5 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -44,6 +44,7 @@ 
 #define MAX_TREE_SIZE (2 + MAX_SERVER_SIZE + 1 + MAX_SHARE_SIZE + 1)
 #define MAX_SERVER_SIZE 15
 #define MAX_SHARE_SIZE 80
+#define MAX_DOMAINNAME_SIZE 256	/* maximum fully qualified domain name (FQDN) */
 #define MAX_USERNAME_SIZE 256	/* reasonable maximum for current servers */
 #define MAX_PASSWORD_SIZE 512	/* max for windows seems to be 256 wide chars */
 
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index fa68813..3f9dcf7 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -1675,7 +1675,8 @@  cifs_parse_mount_options(const char *mountdata, const char *devname,
 			if (string == NULL)
 				goto out_nomem;
 
-			if (strnlen(string, 256) == 256) {
+			if (strnlen(string, MAX_DOMAINNAME_SIZE)
+					== MAX_DOMAINNAME_SIZE) {
 				printk(KERN_WARNING "CIFS: domain name too"
 						    " long\n");
 				goto cifs_parse_mount_err;
@@ -2276,8 +2277,8 @@  cifs_put_smb_ses(struct cifs_ses *ses)
 
 #ifdef CONFIG_KEYS
 
-/* strlen("cifs:a:") + INET6_ADDRSTRLEN + 1 */
-#define CIFSCREDS_DESC_SIZE (7 + INET6_ADDRSTRLEN + 1)
+/* strlen("cifs:a:") + MAX_DOMAINNAME_SIZE + 1 */
+#define CIFSCREDS_DESC_SIZE (7 + MAX_DOMAINNAME_SIZE + 1)
 
 /* Populate username and pw fields from keyring if possible */
 static int
diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c
index 79358e3..57b1537 100644
--- a/fs/cifs/sess.c
+++ b/fs/cifs/sess.c
@@ -197,7 +197,7 @@  static void unicode_domain_string(char **pbcc_area, struct cifs_ses *ses,
 		bytes_ret = 0;
 	} else
 		bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, ses->domainName,
-					    256, nls_cp);
+					    MAX_DOMAINNAME_SIZE, nls_cp);
 	bcc_ptr += 2 * bytes_ret;
 	bcc_ptr += 2;  /* account for null terminator */
 
@@ -255,8 +255,8 @@  static void ascii_ssetup_strings(char **pbcc_area, struct cifs_ses *ses,
 
 	/* copy domain */
 	if (ses->domainName != NULL) {
-		strncpy(bcc_ptr, ses->domainName, 256);
-		bcc_ptr += strnlen(ses->domainName, 256);
+		strncpy(bcc_ptr, ses->domainName, MAX_DOMAINNAME_SIZE);
+		bcc_ptr += strnlen(ses->domainName, MAX_DOMAINNAME_SIZE);
 	} /* else we will send a null domain name
 	     so the server will default to its own domain */
 	*bcc_ptr = 0;